UPS & BATTERY TESTING Testing a UPS (Uninterruptible Power Supply) battery is essential to ensure reliable backup power during outages. Here's how to properly test a UPS battery: 1. Visual Inspection Check for swelling, leakage, or corrosion. Verify connections are clean and tight. 2. Battery Runtime Test (Load Test) Disconnect non-critical loads. Plug in a device (e.g., lamp or small computer) that draws a known load. Unplug the UPS from the wall (simulate a power outage). Monitor how long the UPS runs before shutting down. Compare the runtime with manufacturer specs. If it's significantly shorter, the battery may be degraded. 3. UPS Self-Test Most modern UPS systems have a built-in self-test function: Press and hold the test or power button (refer to the manual). The UPS will simulate a power failure and run diagnostics. Check the status LEDs or display for results (e.g., 'Battery Good' or error codes). 4. Voltage and Internal Resistance Test (Advanced) Use a multimeter and/or battery tester: Fully charge the UPS. Measure voltage across the battery terminals: For a 12V SLA battery: should be around 12.6–13.0V at rest. Under load, should not drop below 10.5V. Use a battery analyzer to check internal resistance (higher resistance = aging battery). 5. Monitoring Software Many UPS units can connect via USB to a PC. Use manufacturer software (e.g., APC PowerChute, Eaton UPS Companion) to check: Battery health Last self-test results Charge level and runtime estimate When to Replace the Battery Battery fails load or self-test Noticeable decrease in runtime Voltage drops quickly under load Age exceeds 3–5 years (typical lifespan for lead-acid batteries)